Surgical needles are made, one at a time, by a multi-step process involving considerable time, labor, and precision machinery. A brief outline of a typical process for making surgical needles is the following:
Stainless steel wire of the appropriate diameter is strightened and cut to the desired length to form a blank. One end of the blank is die-formed and/or ground to produce a cutting edge or point. The other end is either drilled to form a hollow receptacle for a surgical suture, or it is stamped to form a channel for swaging the suture. The point is sharpened, and the needle is bent As a rule, the final steps are a heat treatment to temper the needle, that is, to increase the hardness without imparting brittleness, and a polishing process. After this, sutures are attached to the needles by any of several means. On additional feature of the prior art process for making surgical needles is that the shape of the needle is limited by what can be done to a piece of wire. As will be apparent below, this invention provides a process that can be used to make any shape that can be drawn in two dimensions.
This multi-step process is acceptable for the production of relatively large surgical needles but with the advent of microsurgery and the need for ever smaller surgical needles, the process has proven to be quite inefficient for the production of small needles having diameters of, e.g., from one to three mils because of the large amount of skilled labor and precision machinery required in handling such small needles individually throughout the various steps of the process leading to attachment of sutures and final inspection.
This invention provides a process that is particularly well adapted to the efficient simultaneous production of large numbers of small size surgical needles.